During a recent bank's information security audit, a coworker and I wrestled with LANguard for the better part of two days trying to figure out why LANguard would freeze during network scanning.  There were several potential culprits including a VLAN setting on the port I was using, a “switch” (which looked just like a little 4 port hub) the company had set up to allow me to use two laptops, etc.  I tried scanning from my laptop, from my VM, from the other laptop, skipping the “switch”, etc.  Finally, I set LANguard to a single thread and noted the scan stopped at the “Enumerate Trusted Domains” step.  The company had two domains, something we don’t often encounter.  I disabled this item in the scanning profile and, presto, the scan ran.  To eliminate any other variables, I turned “Enumerate Trusted Domains” back on and it stalled again.